1. Technical Field
The present invention relates generally to a wear resistant material on a cutting tool and, more particularly, to an amorphous carbon wear resistant material for a reamer.
2. Discussion
Reamers are commonly used to finish a circular passage formed in a workpiece by removing a thin layer of material from the passage wall. Standard reamer configurations include a cutting blade protruding radially outwardly an adjustable distance from the periphery of the reamer and several guide members positioned about the periphery of the reamer body to contact the inner surface of the workpiece during operation. The guide members locate the reamer within the bore so that the axis of rotation of the reamer is substantially aligned with the longitudinal axis of the passage.
The guide members of most reamers are provided with an abrasion resistant surface in order to reduce the magnitude and adverse effects of frictional forces developed between the contact surface of the guide member and the passage wall. The surface provides a contact area on the guide member that has a reduced coefficient of friction, minimizes material build-up, and increases the operational life of the guide member. Commonly, pads formed of a material with high hardness and a low coefficient of friction such as a ceramic or poly-crystalline diamond (PCD) are brazed or otherwise connected to a guide member to define the contact surface of the guide member.
Concerns over tool life and the quality of the reamed surface remain for many such guide members. Moreover, it is difficult and expensive to produce a tool having wear resistant pads brazed or otherwise connected to the guide members. Accordingly, a need exists for an abrasion resistant material that may be simply and economically provided to a reamer to define a guiding contact surface with an adequate service life.